Issue link: http://cp.revolio.com/i/356
48 Feb 2009 48 I f you were trying to design an energy system for a rapidly growing population, it would be hard to do worse than the one we have today. It's brittle — dependent upon unstable regions and massive centralized networks. It's dirty — poisoning us with mercury and heating the atmosphere with carbon. And it's fi nite — we're perilously close to running out of one of our key energy resources, oil. getting away from all of this won't be easy, and we're running out of time to make it happen. but there's also good news: We know exactly what we need to do to get out of this mess, and we have all of the necessary tools at hand. We're at the cusp of a massive transition, from the era of limited, subtractive energy resources to the era of unlimited, renewable energy. For a variety of reasons, we've long relied upon energy resources that have fi nite quantities, and once used, leave us stuck with (often deadly) waste products. These resources were easy to fi nd and cheap to use, but — from a long-term perspective — were never really more than bootstrap technologies, allowing us to get to the point where we could shift to energy resources that are functionally limitless, and entirely renewable. That point is here. The initial set of transition technologies are undoubtedly quite familiar to you: massive wind turbines, collected in wind farms covering hundreds of acres; solar panels on rooftops and in the desert; and the granddaddy renewable technology, hydroelectric generators in dams and waterfalls. All useful and important, but very 20th century. The next wave of renewable energy technologies are all about getting away from the old-style centralized grid and embedding energy generation into all aspects of our lives. 5 pAthS to unliMiteD Renewable Energy JAMAIS CASCIo WIND: GO FLY A KITE gone are the mega-towers and spinning blades. Say hello to the age of kites. on the land, higher-altitude wind power, using kites fl ying at a kilometer or higher, can generate eight times as much power as traditional wind turbines (and going higher, up into the jet stream, can be even better). Kites have a couple of advantages over traditional turbines: The wind is steadier at higher altitudes, and kite-based wind power can be more readily integrated into dense environments. A set of kites can produce about a gigawatt of power in the same space required by an old coal or nuclear plant. on the sea, diesel cargo ships outfi tted with kite sails can cut fuel consumption by up to 50%. A german company, Sky Sails, has already outfi tted two cargo ships as test vehicles. The ships remain in commercial operation, and the preliminary reports have been quite positive. Proximity: on land, next decade. on sea, next fi ve years. Prognosis: Shipping companies will jump on this; land-based power companies may be harder to convince. A 2007 Mit study argued that hot rocks geothermal could meet a signifi cant percentage of uS energy demand — in principle, up to 100%